/**
 * @author CKC
 * @DateTime 2022/3/2 16:23
 */
@SuppressWarnings("all")
public class Test1 implements AA {
    public static Test1 test1 = new Test1();
    public Test1 test2;

    {
        System.out.println("AAAA");
        System.out.println(test2.equals(null));
    }

    static {
        System.out.println("BBBB");
    }

    public void sds() {
        int x1 = AA.x1;
    }

    public static void main(String[] args) {
        Test1 test = new Test1();
        if (test instanceof Test1) {

        }
    }
}

interface AA {//All Filed default type : static final
    int x1 = 0;
    int x2 = 1;
    Integer x3 = null;
}
